Switching mechanism



Feb. 16, 1932. VE, BAUS'CH 1,845,033

swI'rcmNG MECHANISM Filed Feb. 24, 195o /N VEN TOR E. BAuJcH Patented Feb. 16, 1932 l UNITED STATES PATENT OFFICE EWALD BAUVSCH, F BROOKLYN, NEW YORK, ASSIGNOR T0 BELL TELEPHONE LABO- RATORIES, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION 0F NEW YORK SWITCHING MECHANISM Application filed February 24, 1930. Serial' No. 430,503.

- This invention relates to switching mechanisms and more particularly to sequence switches of the manually operated lever type. l In the general construction of lever type switches, particularly those having a center orV normal position and two operate positions, it is common practice to employ crooksprings mounted on the contact spring pileup to maintain the operating lever in its actu- '10 ated position and to aid in restoring it to normal. In switches wherein crook-springs are utilized to actuate a plurality of contact springs simultaneously this type of structure y has proven a very satisfactory circuit con- 16 troller. However, in cases where it is desirable to perform switching operations in a certain sequence and timing, which necessitates the use of camming devices, crooksprings may not be employed to advantage. It has also been observedy that the use of crook-springs as a means for securing the operating lever in its normal position as well as its operate positions is not entirely satisfactory in instances where the switch is subjected to undue shock, jarring or kindred unstandard conditions.

It is the object of this invention to improve the design of sequence switches of thelever e. yl'ihis object is attained in accordance with a feature of the invention by the provision of a spring controlled mechanism which insures a positive normal position of the operatin lever and safeguards against accidental isturbance of the lever when in its normal or operate positions.

The switching mechanism of this invention comprises essentially spring sets which are cam operated through the medium of a manually actuated lever, the cams being so shaped as to furnish a predetermined timing and sequence o f the switching operations. The mechanism which insures a positive center or normal position ofthe operating lever consists of a oating member, hereinafter referred to as a cam ring, mounted on two pins rigidly secured to and extending from an operating lever, and spring tensioned at its mid-point to a trunnion extending from the switch mounting plate through the medium of a coil spring.

The invention will be more clearly understood from the following detailed description made with reference to the accompanying drawings in which Fig. 1 is a front elevation of a switching device embodying the features of the invention; Fig. 2 is a similar view of the switch structure shown in Fig. l, in one of its actuated positions; Fig. 3 is a side elevation of the switch shown in Fig. 1.

Like characters throughout the several views designate similar parts. The frame work of the switch comprises a designation plate 5 and a substantially U- shaped bracket provided at its midpoint with two vertically extending flanges 7 and 8 which serve as supports for the spring pileups, and two smaller horizontally extending flanges 9 and 10 which are made fast to the designation plate 5 by means of screws or rivets such as l1 and 12.

A main pivot or axis 13 extends from one side of the U-shaped bracket 6 to the other and serves as a support for the arms 14 and 15 which, with the finger grip 16, constitute the operating lever. A screw 17 passes between the lever arms 14 and 15 near their lower ends and serves as a mounting for the contact spring controlling cams 18 and 19. Secured to one of the lever arms 15 are two Shock absorbing buffers 2O and 21, which engage with the designation plate 5 when the swltch is in its operated positions.

Mounted on and insulated from the frame flanges 7 and 8 are sets of contact springs each having a transfer spring such as 22 resting on a cam such as 19. Vhen the operating lever is actuated, the end of the transfer spring rides on the surface of its associated cam, making or breaking contact with associated contact springs depending upon the contour of the cam.

The oating cam ring 23 is loosely mounted 95 on two grooved metallic roller studs or pins 24 and 25 which are rigidly secured to the lever arm 15. A spiral spring 26 has one end hooked to the lower mid-point on the cam ring and the other end secured to the 100 trunnion 28 integral with the mounting bracket 6.

As shown in Fig. l the switch is in its normal position and is positively held in this position by the force exerted by spring 26. This force is equally distributed between the roller pins 24 and 25 and as these pins are located on either side of the center line of the switch` which passes vertically through the axis 13, the switch leverV is firmly heldl in its center or normal position and will withstand considerable shock or accidental knocks without being disturbed. By increasing the distance of the pins 24 and 25 `from the switch center line the tendency for the switch lever to maintain its normal position is augmented.

Vhen the switch is actuated as shown in Fig. 2 thepins 24 and 25 follow the movementV of the lever and in so doing the pin 24 being confined in the notchedected by the projecting.cammingA surface 30, carries the cam ring with it, the camming'surface 30 riding over the groove in roller pin 25. ln this position it is evident that the force exerted by the spring 26 is concentrated upon pin 24 and as this pin is nowV located to the left of pivot 13 the lever will be locked in its operated position. Y A

Should it be desirable to render the switch locking in its normal position and non-locking in its operated position, the pins 24and 25 would bek separated by a greater distance so that when the lever-was actuated to its operating position the pin 24 would belocated to the right of the center line drawn vertically throughthe pivot 13. `Then the torce vexerted by the spring 26 concentrated on the pin 24 would tend to restore the lever to normal. 'i

Vrlhe descriptions of the two functions just given have been directedto the switch when actuated to the left as shown in Fig. 2'; it is obvious that the same eects are produced when the switch is actuated to the right.

From the Jforegoing description it is apparent that this locking mechanism is ilexible to such an extent that a switch may be rendered locking or non-locking in its operate positions and that a positive center position of the lever is always assured. The positions of the pins 24 and 25 relative to a vertical center line drawn through theaxis V13 determines the locking characteristics Vof the switch.

What is claimed is:

l. In a switching mechanism, an operating lever having a normal position and an operating position and vmeans for automatically centering said Alever in its normal position upon itsV release from its operating position.

2. In a switching mechanism, a lever adapted to actuate contact springs through the medium of a cam, a pivot support for said lever, a spring 'for influencing the movement of said lever, whose line of action normally coincides with the vertical center line of said switching mechanism and means effective upon the actuation of said lever for shifting the line of action of said spring.

3. In a switching mechanism, a lever adapted to actuate contact springs through the medium of a cam, a pivot support for said lever, a spring for influencing the movement of saidlever, whose line of action normally 'coincides with the vertical center line of said switching mechanism and a floating member mounted on a two-point support on said lever vand Vin engagement with said spring, effective upon the actuation of said lever for shifting the line of action of said spring.

Y 4'. In a switch structure, an operating lever, a pivot mounting for said lever, a spring for inuencing the movement of saidy lever, and means intermediate saidk spring vand said lever for distributing the force exerted by said spring on said lever evenly on each side of said pivot mounting when said lever is in its normal position. f Y

5.- ln a switch structure, an operating lever having a normal and operate position, a pivot mounting for said lever, a spring for influencing the movement of said lever,.and means intermediate said spring and said lever for conning the force exerted by said spring on said lever to one side of said pivot mounting when said lever is in its operate position.

6. In a switch structure, an operating lever having a normal and operate position, a pivot mounting for said lever, a spring for influencing the movement oi said lever, and means intermediate said spring andsaid lever for distributing the force exerted by saidspring on said lever evenly on each side of said pivot mounting whenisaid lever` is inits normal position and contining the :torce exerted by said spring on said lever to'one side of said pivot mounting when said lever is in its operate position. l L

7. In a switch structure, an operating lever having Va normal and an operate position, a pivot mounting for said lever, a spring for iniiuencing the `movement of said lever, and a cam ring floatingly moimted on two pins extending :trom said rlever and in engagement with said spring, the positions of the mounting pins relative to Vsaid pivot 'amounting determinating the influence of said spring on said lever. l-

8. Ina switch structure, a mounting frame, an operating lever pivotally supported on said mounting frame, a plurality of cams rigidly secured to'said lever, VContact springs secured to said mounting frame and having a contact arm normally in engagement with said camsor actuating said contact springs in :response to the'operation of said operating lever and means for exertinga pull on said lever ateach side of its-pivotal support to insure a positive center position of said lever when in its'lnormal posit-ion.` i

9. In a switching mechanism a lever adapted to actuate contact springs through the medium of a cam, a pivot support for said lever, a spring for influencing the movement of said lever whose line of action normally coincides with the vertical center line of said lever and means effective upon the actuation of said lever for shifting the line of action with respect to the center line of said lever.

In witness whereof, I hereunto subscribe my name this 17th day of February, 1930.

EWALD BAUSCH. 

